Back to Search Start Over

SN 2020bqj: a Type Ibn supernova with a long lasting peak plateau

Authors :
David R. Williams
B. Rusholme
E. C. Kool
Michael Porter
Lin Yan
Jesper Sollerman
Melissa L. Graham
V. Z. Golkhou
Daniel J. Reiley
David A. Green
Yashvi Sharma
Hector P. Rodriguez
Jakob Nordin
Stephen Kaye
Itai Sfaradi
Dmitry A. Duev
Leonardo Tartaglia
E. S. Phinney
Cristina Barbarino
Y.-L. Kim
Frank J. Masci
Kaushik De
Emir Karamehmetoglu
Ragnhild Lunnan
Daniel A. Perley
J. van Roestel
Maayane T. Soumagnac
T. M. Reynolds
Eric C. Bellm
Assaf Horesh
Steve Schulze
Kirsty Taggart
Christoffer Fremling
Russ R. Laher
Institut de Physique des 2 Infinis de Lyon (IP2I Lyon)
Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Claude Bernard Lyon 1 (UCBL)
Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)
Source :
Astron.Astrophys., Astron.Astrophys., 2021, 652, pp.A136. ⟨10.1051/0004-6361/202039137⟩
Publication Year :
2020
Publisher :
arXiv, 2020.

Abstract

Context: Type Ibn supernovae are a rare class of stripped envelope supernovae interacting with a helium-rich CSM. The majority of the SNe Ibn reported display a surprising homogeneity in their fast lightcurves and starforming hosts. Aims: We present the discovery and study of SN 2020bqj (ZTF20aalrqbu), a SN Ibn with a long-duration peak plateau lasting 40 days and hosted by a faint low-mass galaxy. We aim to explain its peculiar properties using an extensive data set. Methods: We compare the evolution of SN 2020bqj with SNe Ibn from the literature. We fit the bolometric and multi-band lightcurves with different powering mechanism models. Results: The risetime, peak magnitude and spectral features of SN 2020bqj are consistent with those of most SNe Ibn, but the SN is a clear outlier based on its bright, long-lasting peak plateau and low host mass. We show through modeling that the lightcurve can be powered predominantly by shock heating from the interaction of the SN ejecta and a dense CSM. The peculiar Type Ibn SN 2011hw is a close analog to SN 2020bqj, suggesting a similar progenitor and CSM scenario. In this scenario a very massive progenitor star in the transitional phase between a luminous blue variable and a compact Wolf-Rayet star undergoes core-collapse, embedded in a dense helium-rich CSM with an elevated opacity compared to normal SNe Ibn, due to the presence of residual hydrogen. This scenario is consistent with the observed properties of SN 2020bqj and the modeling results. Conclusions: SN 2020bqj is a compelling example of a transitional SN Ibn/IIn based on not only its spectral features, but also its lightcurve, host galaxy properties and the inferred progenitor properties. The strong similarity with SN 2011hw suggests this subclass may be the result of a progenitor in a stellar evolution phase that is distinct from those of progenitors of regular SNe Ibn.<br />Comment: 22 pages, 14 figures, 5 tables. Accepted for publication in Astronomy & Astrophysics. Abstract abridged for arXiv submission

Details

ISSN :
14320746
Database :
OpenAIRE
Journal :
Astron.Astrophys., Astron.Astrophys., 2021, 652, pp.A136. ⟨10.1051/0004-6361/202039137⟩
Accession number :
edsair.doi.dedup.....334bcfa3a3c4246792f2294fba596058
Full Text :
https://doi.org/10.48550/arxiv.2008.04056